Track 2 - Internet Routing and IP Network management (7-Oct-96)
Multicast
3) Protocols
E) Core Based Trees
- Join toward pre-known fixed point in network as core
- limits expansion of multicast transmissions to precisely the set of all recipients.
- Better than Reverse Path Forwarding (DVMRP)
- Scaling depends on number of groups (*,G) not (S,G) in DVMRP
- CBT using spanning tree
(see Radia Perlman on bridges (link layer) spanning tree algorithms)
- CBT has problem that all traffic goes toward that core
- Requires Changes to IGMP (Join, Leave)
- CBT has pre-defined Rendezvous-point, PM defines by configuration
- Tony Ballardie has proposed CBT